1. Field of the Invention
The present invention relates generally to devices for controlling the direction and speed of aircraft and, more particularly, to a flight control apparatus and method for controlling the direction and speed of flight of an aircraft in response to movement of a pilot's body relative to the aircraft.
2. Discussion of the Prior Art
The sport of hang gliding involves flying through the air suspended by a harness beneath a large type of kite or glider constructed especially for the purpose. In order to turn a conventional kite, a pilot is required to shift his body relative to the kite in the direction of the desired turn, thus loading the inner wing causing the non-rigid wing material to billow relative to the outer wing. This change in the shape of the wings and the relative inequalities in the wing loading creates more lift and less drag in the outer wing so that a turn is initiated toward the inner wing. A turn in the opposite direction is carried out in an identical fashion by the pilot leaning in the opposite lateral direction.
In order to slow the flight speed of the kite, the pilot pushes his body rearward relative to the glider by pushing forward on a control bar forming a part of the kite. This action increases the angle of attack of the wings causing the glider to slow. Thus, the kite slows when the pilot moves rearward of a centered position increasing the angle of attack and accelerates when the pilot moves forward decreasing the angle of attack.
This conventional operation remains useful where kites or gliders are constructed with non-rigid, flexible wings which billow when loaded as discussed above. However, glider designs have evolved which provide much higher performance than traditional "kites". These gliders are constructed with tighter, stiffer wings in order to increase the lift and speed of the gliders. As this development work has proceeded, designers have become aware of a trade-off between such high performance characteristics, and handling of the glider.
Specifically, as a glider design is modified to tighten or stiffen the glider, the glider becomes naturally resistive to roll and is more difficult for a pilot to handle. In contrast, if a glider is designed for ease of handling, it is not as tight, having a higher drag than high performance gliders as well as less lift.
Although most pilots cope with the increased roll resistance of high performance gliders by employing different turning techniques than those used with more friendly gliders, it would be desirable to provide a flight control apparatus that would improve handling of high performance gliders while permitting the pilot to employ the same turning and speed control techniques used with lower performance gliders.